Wire drawing machine



Feb. 10, 1942. F. P. DAHLSTR'OM 8 WIRE DRAWING MACHINE Filed July 24,1940 s Sheets-Sheet 1 INVENTOR. fkA VK RDAHLSTIQO/Y I rokzve Y5.

4 Feb. 10, 1942.

F. P. DAHLSTROM WIRE DRAWING- MACHINE Filed July 24, 1940 3 Sheets-Sheet2 INVENTOR. F4Nlf 2 m zsreom OENEYS.

Feb. 10, 1942. F. P. DAHLSTROM WIRE DRAWING MACHI NE Filed July 24, 1940 3 Sheets-Sheet 5 INVENTOR. FFA/VK P. oAHzsrkon Patented Feb. 10, 1942UNITED. STATES; PATEN T OFFICE.

- WIRE DRAWING MACHINE Frank P. Dahlstroni, Woodbridge, Conm, assignorto The Aetna-Standard Engineering Company, Youngstown, Ohio, acorporation of Ohio Application July 24, 1940, Serial No. 347,259 I I 12Claims.

pensate approximately for the elongation of the' In the machine of wirein the successive drafts.

tionof the machine shown in Fig. 1.

the Connor patent the drums are arranged to permit an accumulation ofwire thereon to allow steady operation of the machine for some time,

even though the speeds of the various drums are not in exact proportionto the elongation of the wire. It has been proposed, as disclosed in theapplication of Jerome R. George and Kenneth B. Lewis, Serial No.281,666, filed June 28, 1939, to provide individual electric motordrives for the various blocks or drums in machines of the 'Connor typewhereby the operator of the machine can control the speeds of theindividual drums so that the machine can' be regulated to maintainsubstantially constant accumulations .which is simple anieiiective'andsubstantially x Furthenobjeetsand advantages of my inyentionwfllbecome'apparentfrom the folfoolproof.

lowing description 01f I a a preferred form thereof,

reference being made to the accompanyingdraw ings. The essential.characteristicsare set forth in-the claims. Referring to the bodying myinventionand including three dies and associated blocks. Fig. 2 is a.front eleva- I I Fig. 3 is a sectional detail taken along the line of 33in Fig. 1 but with the block rotated through 90"for. convenience ofillustration. Fig. 4 is a detail of part of the automatic controlmechanism shown in Fig. 3, as indicated by the line of wire on thevarious drums, with the result that I the machines can be operatedcontinuously for definitely long periods of time without the necessityof running ofi the wire on the blocks .and rethreading the machine atrequent intervals, as is required by the original Connor type ofmachine. I

It is a general object of the present invention to provideacontinuous'wire drawing machine constituting a further improvement onmachines 4-4 of Fig. 3, and Fig. 5 is a diagram of the electric circuitsfor the automatic control.

The machine illustrated in Figs. 1 and 2 may be of the general typedescribed and claimed in I I my copending application Serial No.285,338, filed July 19, 1939, and maybe built up by assembling anumberof generally similar. units l0,

II and I2, each unit being provided with die boxes indicated at l4, l5and I6 for supporting suitable wire drawing dies Ma, Ma and Ilia, and Ithe units embodying blocks or drums I 8, I9 and 20, respectively. Theblocks or drums preferably are driven by independent variable speed.motors 22, 23 and 24 through any convenient gearing or. power;transmitting mechanism such as that illustrated in my aforesaidapplication. Inasmuch as this mechanism and the mode of supporting theblocks on the frames of the vunits form, per se, no part of the presentinvention,

' no further description of these parts of the appaof the typeillustrated for example in the Connor patent and in which automaticmeans are provided forcontrolling the speed of the various I drums. ofthe machine so that the machine will be operated in such fashion thatsubstantially equal weights of wire will be drawn through the diesassociated with each block or unit for any given period of time. By thisarrangement the accumulations of the wire on the blocks of the machine(except for the finishingblock) remain substantially constant and themachine can be operated continuously-with a minimum amount of attentionbeing required.

Another object of my invention is to provide a simple and effectivemechanism for -'automatically controlling the speed of the blocks ofwire drawing machines. Afurtherobject is to provide an automatic controlmechanism;

ratus will be given in the present specification.

The units are arrangedin line as shown in Figs. 1 and 2, the wire Wbeing drawn through the die bo-x l4 and its associated die Ma onto thedrum'or block I8 where it is wrapped tightly around the portion 26, Asmore wire is drawn on to the block, the coils are moved upwardly,

surrounding the'reduced portion 21. In thread-I ing the machine, aconsiderable number of turns of wire are accumulated'on the block, so'as to permit the wire to cool and rest between' successive drafts. The'wire'is taken off the block in a enerally axialdirection over thesheave 28 f I Carried y an arm 29 .which is mounted fo'r'r'ota-" tionabout an axis aligned with the axis of the block 18 in a manner to bedescribed in detail below. "The wire is then carried upwardly and guidedover the pulley 32 'disp'osedabove thedrawings, Fig. 1 illustrates a topplan view of a wire drawing machine em;

center of the drum l8, thence downwardly and around the pulley or sheave33 to the die box l where it is drawn through another die on to the drumor block H of substantially identical construction with the block is. v

The wire is led away from the block IS in the same manner as from theblock l8, that is, it is carried over the pulley 34 supported by the arm35, over pulleys 3G and 3! to the die-box l8 and its associated die. Thewire is drawn through the die box it and die lilo on to the finishingdrum or block'lll which is of slightly different construction, in thatit is provided with axially extending bars 38 for retaining a coil ofwire of considerable size on the drum, the bars and coil being protectedby a wire guard 35. The finishing unit is also preferably provided withan upwardly extending arm or bracket All adapted to support a hoist forremoving the coil of wire from the finishing block.

In general, the three units may be of substantially identicalconstruction so far as the supporting frames and driving mechanisms areconcerned, The motors of units l6 and H are controlled by motor-drivenrheostats M and 42, while a manually-operated rheostat 43 is providedfor controlling thespeed of the motor 2%,

around in a clockwise direction. On the other I hand if the wire isbeing removed from the block Different gear ratios may be employedwithin the units as the drum of each succeeding unit must be operated ata higher rate of speed than the speed of the preceding unit due to thereduction and corresponding elongation of the wire as it passes througheach succeeding die. The die box on the first unit ill is arrangedslightly difierently than the'die box on the remaining units and thefinishing unit employs a block or drum of somewhat different characterand the guide pulleys are eliminated. from the finishing block.Generally speaking, however, the units preferably are of substantiallyidentical construction, and as those skilled in the art will understand,it is not necessary to employ precisely three blocks or units, but theinvention is useful in cornunction'with a machine embodying only twoblocks, as well. as with a machine embodying more than three blocks.Further, the blocks need not be mounted on separate units, but may allhe supported on a single bench or frame.

it is a characteristic of machines of this type that so long as wire isbeing removed from a blockat the same rate at which it is being drawn onto the block, then the guide over which the wire is withdrawn from theblock will remain stationary. That is, for example, if the relationshipbetween the speeds of the blocks is and Eli and the diameters of thewire after it has been drawn through the dies Mo and Etc are such thatthe same weight of wire is drawn through both dies per unit of time,then the wire will be drawn on to the block it at precisely the samespeed at which it leaves the block it over the sheave 28. Thus the samenumber of turns of wire will remain on the block ill, and the bracket 29and the pulley 28 will remain stationary with respect to the centralaxis of the block.

If wire is being withdrawn from the block faster than it is beingsupplied thereto, then the number of turns of wire on the block. will bereduced and the bracket 29' and pulley 28 will rotate around thecentral'axis of the block in a direction opposite to the rotation of theblock, that is, in the drawings the block it? is driven in acounter-clockwise direction and under these circumstances the guidepulley 28 will swing at a slower rate than it is being drawn on to theblock and accordingly, wire is being accumulated on the block, then theguide pulley 28 and bracket 28: will swing around the central axis ofthe block in the same direction as the direction of rotation of theblock but at a slower speed.

I employ this characteristic motion of the guide over which the wire iswithdrawn from the blocks to actuate'the automatic control mechanism forthe speed of the motors driving the various blocks. That is, through amechanism to be described in detail below, the rheostats 4i and 42,which control the motors 22 and 23 respectively, are automaticallyadjusted in response to movements of the pulleys 28 and 34, associatedwith the blocks l8 and I9 respectively, to control the speeds of themotors so that under ordinary operating conditions substantially thesame number of turns of wire willremain on the blocks l8 and Is at alltimes, the motordriving either block being automatically adjusted withrespect to the rate at which the wire is withdrawn to a succeeding blockto insure that the wire is drawn on to and removed from the blocks atsubstantially the same speed.

In the embodiment shown 'in the drawings, the speed of the finishingblock may be manually adjusted to a given value. Then the speed of themotor 23 will be automatically adjusted so that the block it willfunction to draw the wire through the die Elia at substantially the samespeed that the wire is removed from the block IS to the die Mia and thefinishing block 20. Similarly, the speed of motor 22 will beautomatically adjusted so that the block ill will be driven at such aspeed, depending upon the reduction eifected by the die 65a, that thewire will be drawn through the die Ma and on to the block it atsubstantially the same speed that it is removed from that block tosupply wire to the die Elia as demanded by the operation of the block.l5.

A preferred form of automatic mechanism for so adjusting'the speeds ofthe motors and blocks is illustrated in the drawings. The mechanismassociated with unit ill will be described, it being understood that thecontrol mechanism is preferably identical for units ill and. it, or, ina machine embodying more than three blocks, for all blocks except thefinishing block.

As shown in Fig. 3, the pulley 2% is supported by a bracket 29 whichinturn is secured to an annular flange d5 extending from a hub 46. Thehub is supported by suitable bearings 41 upon the upwardly extendingshaft t8 which-is rigidlyniounted upon the block l8 and is coaxialtherewith. Thus the bracket 29 and pulley 28 are free to swing aroundthe shaft 48 and the pulley can properly guide the wire being withdrawnfrom the block regardless of any variation in rate of operation of themachine.

To tension properly the wire as it is being withdrawn from the block andto urge constantly the pulley into engagement with the wire, Ipreferably employ afriction drive which tends to rotate the hub andpulley in the direction of rotation of the block. This may comprise anannular plate 50 having an annular disk H of suitable friction materialsecured thereto, the friction material engaging the flat annular surface52 formed on the upper part of the block II. The annular plate 50 has athreaded substantially cylindrical portion 53 extending upwardly down onthe embodiment block 3 will be driven at the proper 7 2,272,187therefrom, the internal threads on the cylindrical portion engagingexternal threads formed on the hub member 45, as indicated at 54. Thedriving engagement between the annular member 55 and the hub 45-isthrough the coil spring 55 which surrounds the cylindrical portion 53,

mounted on the annular flange 55 while the other end of the springengages one of the series of pins 51, disposed in openings 58 in theupper flange 45. I I

By engaging the end 55 of the springwith different pins, the forceexerted by the spring may be adjusted and correspondingly the frictionalengagement between the friction material and the surface 52 may bevaried by the adjustment of the spring. The arrangement is such that theclockwise direction.

one end of the spring engaging the screw 55 I flange rotates ina'clockwise direction and decreased when the flange rotates in acounter- Any suitable mechanism -may be employed for effecting thisresult, a preferred form of mechanismcomprising the motor drivenrheostat 4| which controls the fied current of the motor 22 and which inturn i controlled by the switches 5| and 52. These switchas are operatedby cams 55 and 54 engaging the switch levers 55 and 55, the cams beingmounted upon a shaft 51 supported by asuitable bearing 55 preferablymounted on the upright plate 55 forming part of the frame of the unit.The shaft is rotated,either to leave both switches in the off positionor to close one or the other, by means of action of the spring betweenthe pin 51 and the screw 55 tends to rotate the threaded sleeve 55with-respect to the threaded hub 45 in a direction to urge the frictionmaterial downwardly into engagement with the surface 52, that is,looking illustrated, if the pulley and flange are held stationary by thewire, the spring tends to rotate member 50 in a clockwise direction;however, this action is opposed by the counterclockwise rotation of thedrum, which, a

through the friction material 5|, tends to rotate the member 55 incounter-clockwise direction and thus to reduce the pressure of.thefriction material against the surface 55. Thus the friction drive isdependent on the adjustment of the spring and friction of the frictionmaterial against the sur- .face 52; with the result that the drive isautomatically balanced in operation to maintain a tension in thewireproportional to the torque exerted by the spring between the members50 and 45. By this means the force tending to rotate the upper flange 45and thus .to swing the pulley about the axis of the block, andcorrespondinglythe tension onthe wire can be accurately controlled. Inorder to make for easy adjustment of the spring, the end engaging thepin 51 is pref-- erably extended outwardlybeyond the limits of theflange 45, to provide a convenient handle.

By this construction a simple and effective friction drive is provided,whereby the pulley is always urged to rotate in a direction of rotationof the blocker drum, l5, but whereby slippage can take place between theparts whenever the tension on the wire engaging the pulley exceeds apredetermined amount, which may be adis independent of the coeflicientof rection, for example, will result in closing the a lever 1| supportedon pins 12 and 13 which are carried by the collar 14 keyed to the shaft51. The leverextends downwardly and engages-the peripheral edge of aring 15 mounted upon the flange 45 and rotatable therewith. Rotation ofthe flange 45 will thus result in therotation of the ring 15 which byfrictional engagement will cause the lever- 1| to swing in one directionor the other depending upon the direction of rotation of v the flangeand ring. The lever is urged into frictional engagement with the ring bythe spring 15 acting between the upper end of the lever 1| and thewasher 11 mounted on the upper pin 13. The

compression of the spring may be regulated by adjusting thepositior ofthe, washer on the pin. By this arrangement the lever 1| and theswitches. 5| and 52 may be actuated immediately in response to movementof theflange 45 and ring 15, but continued rotation of the ring can haveno damaging effect and willresult'in only slight wear,fortheconstruction is such that as the lever 1| is swung from itsvertical position towards the extreme positions indicated in brokenlines at H in Fig. 4, the pressure of the lever against the ring isgradually reduced'until in the extreme positions the pressure may bevery slight.

The electrical connections are illustrated dia-' grammatically in Fig.5'where it will beseen that swinging the lever 1| to the left inresponse to rotation ofthe ring I5 in counter-clockwise dicircuitthrough the switch'5 2. When this circult is closed, current will flowfrom the direct current supply main 15 through the conductor 5|, limitswitch 52, switch'52, the fleld coil 55 of the rheostat motor. 55 andthence through the justed by the adjustment of the spring 55. The

tension on the wire is kept substantially constant for any givenadjustment and any difference in the relative speeds at which the wireis beingdrawnon to and withdrawn from the block is promptly reflectedand the swinging of the pulley 25 about the axis of the block. In theapparatus shown in the by rotation of the flange 45 the arm 55 of therheostat 4| being swung in a drawings, the .pulley andflange will movein a 7 clockwise direction when the block is running too slowly, andmove in a counter-clockwise direction when the block is running too fast(accumulating wire) with relation to the rate at which the wire is beingwithdrawn therefrom.

The rotation of the flange and pulley is utilized of the motor 22 sothat the speed with respect to the speed of the succeeding block |5 soto control the speed that the accumulation of wire on the block' l5 willremain substantially constant. This is accomplished by connectionsbetween the flange and the controls for the motor 22 whereby thearmature of the rheostat motor to the direct current supply line 55.This will result in the operation of the rheostat motor. 55 in adirection to decrease the speed of the main driving motor 22,

direction to'de'crease the resistance in the fleld circuit of the motor22 and thus decrease its speed. Likewise if the lever 1| is swung to theright in response to clockwise rotation of ,the ring 15, the circuitwill be completed through the switch 5| and limit switch55 (shown inopen speed of the motor 22 is increased when the the rheostat comes tothe end of its travel. This is accomplished by an extension on therheostat arm 88 which engages the switches inthe extreme positions ofthe arm. In the; diagram shown the rheostat is at the position for thehighest speed of operation of the motor 22, the circuit being from theD. C. supply line through the conductor 8| and all of the resistance ofthe rheostat to the rheostat arm 88 and from the arm throughthe-conductor 88 and the field 8| of the motor 22 back to the supplyline 88. The arm 88 has opened switch 88 and stopped further operationof the rheostat motor in that direction, although the motor is ready foroperation in response to closing of switch 82, to decrease the speed ofmotor 22. Thus no damage can take place to the'rheostat or theassociated mechanism even though the friction ring II should continue torotate in the same direction for a considerable length of time. Thisaction may occur under various conditions of operation of the machine,particularly when the machine is being threaded and put into operation.

.As stated above, the automatic control mechanisms for units I8 and -IIand their associated blocks I8 and I8 are substantially identical. Thoseskilled in the art will appreciate that an automatic control mechanismis not required for the finishing block 28, amanual control for themotor 24 driving this block preferably being provided. This control maycomprise a rotatable control knob 82 secured to a shaft 83 extending tothe rear of the unit where it is provided with a sprocket 84 connectedby a chain 85 to a sprocket 96 mounted on the shaft of the hand.

operated rheostat 43. Thus the rheostat 43 and the speed of the motor 24may be conveniently may be used to correlate the speed of that blockwith the speed of operation of the succeeding block I8.

The wire leaves theblock I8 over pulleys 34, 88 and 81 and is ledthrough thefinishing, die IM to the finishing'block 28. As soon aswillcient wire has been accumulated on the finishing block 28 to givesuflicient frictional engagement between the block and the wire topermit the wire to be drawn through the finishing die, the tongs can beremoved and the operation of the machine can be completely automatic.All of the motors are then put on their normal speed operation. Thespeed of the finishing block is manually adjusted ,to the desired rateby means of the control knob, and by means of the automatic mechanismsheretofore described, the

speeds of the blocks I8 and I8 are automatically correlated with thespeed of the finishing block, the ultimate speeds of these blocksdepending upon the relationship between the various diameters of thewire as it is drawn through the several dies.

Each of the units is provided with manual v means such as conventionalpush-button switches (not shown) for starting and stopping therespective motors and preferably the switches are arranged to operatethe motors either at a slow speed for threading or at normal speed, inwhich latter case the speed of the motors is controlled by therespective rheostats associated therewith. These controls may be of anywell-known type. In addition to the push-button control the units arepreferably provided with bars I81, I82 and I83 respectively which areconnected with switch mechanisms of any convenient type so that a pushon any one of the bars will result in the stopping of the entiremachine.

In operation the machine is threaded in the usual manner, that is, thewire or rod to be drawn, with a suitable point formed thereon, is firstinserted through the die Ila, then by means of the usual tongs, is drawnaround the drum I8 until the frictional engagement between the drum andthe wire is suflicient to pull the wire through the die. The tongs arethenremoved and the desired number of turns are accumulated on the blockl8. The wire is then led around the pulleys 28, 82 and 33, threadedthrough-the die lie and wound on the drum I8. The threading operationsinitially are carried out at slow speed of the motors, but if desired,the automatic control mechanism associated with the block I8 In'use, theautomatic speed adjustment functions to bring the motors to proper speeda short time after the machine has been threaded and is operatingnormally. In long runs, the adjustments of the rheostats willautomatically change in responseto changes in elongation occasioned bywear of the dies or changes in the characteristics of the material.However, these factors are all taken care of automatically as the needfor adjustment arises. Accordingly, the machine may be operated for longperiods of time so long as a continuous supply of wire is available tothe first unit.

The automatic speed control of the machine increases the rate ofproduction, and improves the efliciency of power utilization. Themachine is also advantageous in that time is given between thesuccessive drawing operations to permit the wire to cooland rest, whichgives improved results, particularly with some types of alloys.

The foregoing description of a preferred form of my invention is givenby way of example, it being evident that various changes andmodifications in the preferred form described herein can be made bypersons skilled in the art without departing from the spirit andteachings of my'invention. Therefore, it is to be understood that mypatent is not limited to the preferred embodiment described herein or inany manner other than by the scope of the appended claims when given therange of equivalents to which my patentmay be entitled.

I claim:

1. In a continuous wire drawing machine comprising a plurality of dies,a plurality of blocks for drawing wire through said dies, said blocksbeing adapted to carry a reserve or accumulation of wire thereon, andmeans for withdrawing the wire from at least one of said blocks in anaxial direction includinga guide for said wire rotatable about an axissubstantially coaxial with said block, the combination of friction meanstending to rotate said guide in the direction of rotation of said block,the tension of the wire against guidetending to rotate said guide in theopposite direction, and means controlled by the rotation of said guidefor controlling the speed of said block to maintain the accumulation ofwire thereon substantially constant;

in the rates atwhich wire is being drawn onto andwithdrawn from saidblock and means-controlled by the .rotationof said guide for controllingthe speed of said block to maintain the accumulation of wire thereonsubstantially constant. I v

3. A continuouswire drawing machine comprising a plurality of dies, aplurality of blocks for drawing wire through said dies, said blocksbeing adapted to carry a reserve or accumulation of wire thereon, meansfor withdrawingthe wire from said blocks in, an axial directionincluding I a pulley for guiding said'wire, said pulley being swingable,about -an axissubstantially coaxial with said block, friction meanstending to swing said pulley in the direction of rotation of said block,the tension of the wire against said pulley tending toswing said pulleyin the opposite direction, andmeans controlled by the swinging'movementof said pulley for controlling the speed of said block to maintain theaccumulation of wire thereon substantially constant.

4. In a continuous wire drawing machine of the type in which wire may bewithdrawn from a block at a speed difierent from thatat which the wireis being drawn on to the block, a plurality of wire drawing blocks, atleast one of said blocks having independently adjustable means fordriving .said block and means automatically controlled by variations inthe speed at which wire is withdrawn from said block as compared to thespeed at which wire is being drawn on to said block for controlling thespeed of said block so that the speed at which wire is withdrawn fromsaid block will be substantially equal to the speed at which wire isbeing drawn on to said block and ,the accumulation of wire thereon willbe [substantially constant.

5. A continuous wire drawing machine comprising a finishing block, a dieassociated therewith, means for driving said finishing block, manuallyoperable means for adjusting the speed of said driving means, anotherblock preceding said finishing block, a die associated therewith, saidother block being arrangedto retain an accumulation or reserve of wirethereon, independently variable speed means for. driving said other saidother block and controlled by variations in the speed at which wire iswithdrawn therefrom as compared to the speed at which wire is drawn ontosaid-block for automatically adjust-' ing the speed thereof to maintainthe accumulation or reserve of 'wire thereon substantially con- .stantin normal operation of the machine, re-

gardless of normal variations in the speed of said finishing block ornormalchanges in the reduction eifected by the dies.

said block and coaxial therewithjfriction means tending to rotate saidmember with said block, a guide pulley for wire withdrawn from saidblock mounted on said member and -arranged so that engagement of thewire againstthe pulley tends to prevent rotation of said memberandswitch means actuated by said flanged member whereby rotation of saidmember will result in operationof said motor driven rheostat andadjustmentof the speed of saiddriving motor.

'7. In axwire drawing machine, a block for drawing wire through a die, adriving motor for said block, an electrically operated rheostat forcontrolling the speed of said driving motor, a member mounted forrotation with respect to said rotate said member with said block, aguide for wire withdrawn from said block mounted on said memberandarranged so that engagementof the wire with said guide controls therotation of said member,; switch means actuated by said member, andelectrical connections between said switch means andsaid rheostatwhereby rotation of said member will result in operation of saidrheostat and adjustment of the speed of said driving motor, and-a slipconnection between said member and said switch means.

8. In a wire drawing machine having a frame structure, a block fordrawing wire through a die, and a driving motor for said block, thecombination of an electrically operated rheostat for controlling thespeed of said driving motor, a

flanged member 'rotatably mounted upon whenwith said block, a guidepulley for wire withdrawnblock and coaxialtherewith, means tending to"ing carried by said block and coaxial therewith,

from said block mounted on said member and arranged so that engagementof the wireag'ainst the pulley tends to prevent rotation of said member,a ring rigidly mounted on and surrounding.

said flangedgmember and rotatable therewith, a

lever pivotallyemounted on said frame structure and frictionallyengaging'said ring in a region spaced from said pivotal mounting wherebyro tation of said ring will result in a swinging movement of saidlever-in one direction or the other,

depending on the direction of rotation of said ring, switch meansactuated by said lever and electrical connections between said'switchmeans and said rheostat whereby rotation of said ring and flanged memberwill resultfin operation of said rheostat and in increasing ordecreasing the speed of said driving motor, depending on the directionof rotation of said ring.

9. In a wire drawing machine having a frame structure, a blockfordrawing wire through a die, and a driving motor-for said block, thecombination of an electrically operated rheostat for con trolling thespeed of said driving motor, a guide for wire withdrawn from said blockmounted for rotation about the axis of said block, the moveinent of saidguide depending upon the relative rates at which wire is being drawnonto and withdrawn from said block, switch, means actuated by movementof said guide, there being a tween said switch means and said rheostatwhere- 6. Ina wire drawing machine, a block for drawing wire'throughadie, a driving motorfor said block, a motor driven rheostat forcontrolling the speed of said driving motor, a flanged member rotatablymounted upon a bearing carried by by movement of said guide will resultin operaguide.

' 10. In a wire drawing machine having a frame structure, a block fordrawing wire through a die;

, friction connection between said switch means .and', said guide andelectrical connections beand a driving motor for said block, thecombination of an electrically operated rheostat for controlling thespeed of said driving motor, a guide for wire withdrawn from-said blockmounted for rotation about the axis of said block, the movement of saidguide depending upon the relative' rates at which wire is being drawnonto and withdrawn from said block, a ring concentric" with said blockand rotatable with said guide, a lever pivotally mounted on said framestructure and frictionally engaging said ring in a region spaced fromsaid pivotal mounting whereby rotation of said ring will result in aswinging movement of said lever in one direction or the other, dependingon the direction of rotation of said ring, switch means actuated by saidlever and electrical connections between said switch means a and saidrheostat whereby rotation of said ring and flanged member will result inoperation of said rheostat and in increasing or decreasing the drivingsaid member from said friction means and for urging said friction meansinto engagement with said block, and a guide pulley for wire withdrawnfrom said block mounted on said member and arranged so that engagementof the wire against the pulley tends to prevent rotation of said memberand to oppose the action of the spring and thereby tends to reduce thepressure of said friction means against said block, whereby the tensionof said wire may be controlled by adjusting said spring.

-12. In a wire drawing machine having a frame structure, a block fordrawing wire through a die, and a driving motor for said block, thecombination of a rheostat for controlling the speed of said drivingmotor, a guide for wire withdrawn from said block mounted for movementabout the axis of said block, the movement'of said guide depending uponthe relative rates at which wire is being drawn onto and withdrawn fromsaid block, a ring concentric with said block and rotatable with saidguide, means frictionally engaging said ring for controlling saidrheostat whereby rotation of said ring will result in operation of saidrheostat and in increasing or decreasing the speed of said drivingmotor, depending on the direction of rotation of said ring.

FRANK P. DAHIS'I'ROM.

